Ultra short wave apparatus



Aug. 25, 1936. w. DALLENBACH ULTRA SHORT WAVE APPARATUS Filed March 1, 1935 In vento WAL TER DAZLE/VSAC/f Run ATTORNEYS Patented Aug. 25, 1936 ULTRA snoa'r WAVE APPARATUS Walter Diillenbach, Berlin-Charlottenburg, Germany, assignor to N. V. Machinerieen en Apparaten Fabrieken Meaf, Utrecht, Netherlands Application March 1, 1935 Serial No. 8,940 In Germany March 7, 1934 14 Claims. (Cl. 250--11) The present invention relates to an arrangement for coupling a closed line with an open line for ultra-high frequency electro-magnetic waves.

The particular purpose of the present invention consists in constructing an energy line for ultrahigh frequency electro-magnetic waves for connecting aerials with the resonator of generating or receiving tubes, which isfree from radiation losses, which permits aerials, particularly dipole aerials, to be coupled symmetrically with the resonator of the tube and which, moreover,-furnishes the possibility of establishing an optimal coupling between tube and aerial.

The use of closed double lines as well as open double lines as energy lines for ultra-high frequency electro-magnetic waves is known. The closed double lines, consisting of an inner conductor and an outer conductor enclosing the inner conductor, embody the advantage, that they are free from loss radiation at the ends. However, they possess the drawback that they do not permit symmetrical coupling with dipole aerials. The open line, consistingof two parallel conductors disposed in juxta-position, is

characterized, it is true, by the advantage thatit may be symmetrically coupled with dipole aerials but, on the other hand, it is very difficult indeed to couple it with the resonator of a tube 'without the loss of radiation, particularly, however, with resonators designed as a hollow space closed all round.

In order to be able to avoid these difficulties, it is, therefore, suggested an energy'line consisting of an open and a closed double line be employed for ultra-high frequency electro-magnetic waves. The arrangement for coupling the two lines in accordance with the present invention is of such a nature that, in the first instance, the two lines are made to cross each other and, secondly, that the inner conductor of the closed line, projects beyond the end of the outer conductor at the point of coupling or junction like an aerial and penetrates'into the field space of the open energy line.

An example of the present invention is illustrated in the accompanying drawing in which Fig. 1 represents a coupling arrangement in accordance with the present invention in section;

Fig. 2 illustrates the same in perspective; and

Fig. 3 shows in section a coupling arrangement in accordance with the present invention in connection with an ultra-short wave tube, a hollow space resonator and two M2 dipole aerials accommodated within reflectors. As shown in the drawing a particularly symmetrical coupling arrangement will then be obtained, if the two energy lines are made to cross each other in a perpendicular direction, so that the inner conductor of the closed line projects, parallel to the 5 electric field lines, into the field space of the open energy. line.

In the constructional form as shown in Figs. 1 and 2, a double line, consisting of a cylindrical inn-er conductor I and a cylindrical outer con- 10 ductor 2, co-axial thereto, is employed. The open line consists of two parallel band-shaped conductors 3 and 4. The two conductors have been disposed perpendicularly to each other, while the outer conductor 2 is galvanically connected with 15 the band-shaped conductor 3. Through an aperture in the conductor 3 the part 5 of the inner conductor of the closed line partly penetrates, like an aerial, into the field space of the open line.

By means of the corresponding selection of 20 the conductor 5 and the selection of the distance between the conductors 3 and 4, it will be possible 'to vary the coupling between the two energy lines. l a

In order to obviate the possibility that the end 5 5 of the inner conductor I gives ofi loss radiation perpendicularly to the axis of the open line 3, 4, it will b'e surrounded by a screen in form of a cylindrical metal tube 6. It will be appropriate to connect this metal screen galvanically with the 30 outer conductor of the closed line.

In the example of application represented in Fig.3, the free end of the closed line is connected with an ultra-short wave tube 1, while the two free ends of the open line have been coupled with dipole aerials 8 of the length M2. The aerials 8 are accommodated in the focal point of parabolic reflectors 9 being galvanically connected at their vertices with the screening tube 6. The resonator of the ultra-short wave tube 1 is limited by the concentric and cylindrical metal tubes I0 and II being provided at the lower end with a short circuit condenser formed by the flanges I2, I3. At the upper end the tubes III and I I are made to terminate in the conductors I and 2 of the closed energy line. The medium part of the conductor III has been provided with a grid I4, being equipped in its interior with a hot cathode I5 serving as source of electrons. It is impossible that losses of radiation are occasioned along the energy line between tube and aerials.

For the purpose of securing a favourable coupling of tube and aerials, it is advisable to determine the length of the open and of the closed energy line at a certain ratio to the wavelength 55 of the wave to be emitted or received. -In the present example the closed line has been coupled with the resonator in a potential node. In view of the fact, that at the junction at the other end of the closed energy line a potential loop is formed, the length of the closed energy line is advantageously selected so as to equal the quarter wavelength (A/ l) or an odd multiple thereof.

In an identical manner also the length of the open line will have to be selected at a certain ratio to the wavelength. Considering that at the point of coupling of the aerials a potential node will be formed, it is of advantage also to cause the length a of the open energy line between aerial and the junction at 5 to be so constructed as to equal the quarter wavelength or an odd multiple thereof, because just in that case will a potential loop be formed at the junction. If the open energy line terminates in a potential loop, the length a will advantageously be selected so as to equal M2 or an integral multiple thereof.

In the present example the screw IB serves for varying the distance of the parallel conductors 3, 4, in order to be able to vary the surge impedance of the open line and the coupling of the open line with the closed line, so that the aerials are optimally coupled with the tube.

The application of the coupling arrangement in accordance with the present invention is not confined to the example described and shown. Particularly such arrangements may be constructed, in which only one \/2 aerial is coupled with the open energy line, the other end terminating at a suitable distance, bridged galvanically or by means of short circuit condensers. In that case it will be advisable to select the tuning of that part of the conductor, so that at the position of the extended inner conductor 5 a potential loop of the oscillation is produced.

What I claim, is:

1. A coupling arrangement comprising a closed line for ultra-high frequency electromagnetic waves, said closed line consisting of an inner conductor and an outer conductor, an open line for ultra-high frequency electromagnetic waves, said open line consisting of two substantially parallel conductors, said closed and open lines being disposed at an angle to one another, the outer conductor of the closed line being joined to one of the parallel conductors of the open line and the inner conductor of the closed line projecting beyond the end of the outer conductor and into the field space of the open energy line as an aerial.

2. In a coupling arrangement as defined in claim 1, said open and closed lines being disposed perpendicular to one another, the parallel conductor of the open line to which the outer conductor of the closed line is joined having an opening therein for the passage of the inner conductor of the closed line into the field space of the open energy line.

3. A coupling arrangement comprising a closed line for ultra-high frequency electromagnetic waves, said closed line consisting of an inner conductor and an outer conductor, an open line for ultra-high frequency electromagnetic waves, said open line consisting of two substantially parallel conductors, said closed and open lines being disposed at an angle to one another, the outer conductor of the closed line being joined to one of the parallel conductors of the open line and the inner conductor of the closed line projecting beyond the end of the outer conductor and into the field space of the open energy line as an aerial, and a metal screen surrounding said open line.

4. A coupling arrangement comprising a closed line for ultra-high frequency electromagnetic waves, said closed line consisting of an inner conductor and an outer conductor, an open line for ultra-high frequency electromagnetic waves, said open line consisting of two substantially parallel conductors, said closed and open lines being disposed at an angle to one another, the outer conductor of the closed line being joined to one of the parallel conductors of the open line and the inner conductor of the closed line projecting beyond the end of the outer conductor and into the field space of the open energy line as an aerial, and a metal screen surrounding said open line and galvanically connected with the outer conductor of the closed line.

5. A coupling arrangement comprising a closed line for ultra-high frequency electromagnetic waves, said closed line consisting of an inner conductor and an outer conductor, an open line for ultra-high frequency electromagnetic waves, said open line consisting of two substantially parallel conductors, said closed and open lines being disposed at an angle to one another, the outer conductor of the closed line being joined to one of the parallel conductors of the open line and the inner conductor of the closed line projecting beyond the end of the outer conductor and into said field space of the open energy line as an aerial, and means for varying the coupling.

6. A coupling arrangement comprising a closed line for ultra-high frequency electromagnetic waves, said closed line consisting of an inner conductor and an outer conductor, an open line for ultra-high frequency electromagnetic waves, said open line consisting of two substantially parallel conductors, said closed and open lines being disposed at an angle to one another, the outer conductor of the closed line being joined to one of the parallel conductors of the open line and the inner conductor of the closed line projecting beyond the end of the outer conductor and into said field space of the open energy line as an aerial, and means for varying the distance between the conductors of the open line.

7. A coupling arrangement comprising, a closed line for ultra-high frequency electromagnetic waves, said closed line consisting of a cylindrical inner conductor and an outer conductor concentrically enclosing said inner conductor, an open line for ultra-high frequency electromagnetic waves, said open line consisting of two parallel conductors, the outer conductor of said closed line being connected at an angle to one of said parallel conductors, the inner conductor of the closed line projecting beyond the end of the outer conductor of the closed line and into the field space of the open line as an aerial.

8. In a coupling arrangement as defined in claim 7, said parallel conductors being flat and band shaped.

9. A coupling arrangement comprising, a closed line for ultra-high frequency electromagnetic waves, said closed line consisting of a cylindrical inner conductor and an outer conductor concentrically enclosing said inner conductor, an open line for ultras-high frequency electromagnetic waves, said open line consisting of two parallel, flat and band-shaped conductors disposed perpendicularly with respect to said closed line, the outer conductor of said closed line being galvanically connected with a conductor of the open line, the inner conductor of the closed line projecting as an aerial beyond the end of the outer conductor only partly into the field spaceof the open line parallel to the electric field lines, a metal screen enclosing the parallel conductors of said open line and galvanically connected with the outer conductor of the closed line. A

10. An arrangement for emitting or receiving ultra-short electromagnetic waves, comprising an ultra-short wave tube, a. resonator for said tube, an open energy line and a closed energy line; said open energy line consisting of two spaced conductors, said closedenergy line consisting of an inner conductor and an outer conductor surrounding the inner conductor, said open and closed energy lines being coupled together at an angle to one another, the inner conductor of the closed line projecting beyond the outer conductor and penetrating into the field space of the open line, said resonator coupled to said closed energy line, and at least one aerial coupled with the open energy line.

11. In an arrangement as defined in claim 10, means for varying the coupling.

12. In an arrangement as defined in claim 10, means for varying the distance between the conductors making up the open energy line..

13. An arrangement for emitting or receiving ultra-:short electromagnetic waves, comprising an ultra-short wave tube, a resonator for said tube forming a hollow space, an open energy line consisting of two spaced conductors, a closed energy line consisting of an inner conductor and an outer conductor surrounding the inner conductor, means for coupling the two energy lines, said means being such that the inner conductor of the closed line projects beyond the outer conductor and projects into the field space of the open line, means for varying the coupling, a metallic screen surrounding said open line, and di-pole aerials each coupled with one end of the open line, said resonator being coupled with one end of the closed energy line in a radiation-proof manner.

14. An arrangement for emitting and receiving ultra-short electromagnetic waves, comprising a closed energy line consisting of an inner cylindrical conductor and an outer concentric cylindrical conductor surrounding the inner conductor, an open energy line consisting of parallel band-shaped conductors, said closed and open lines being disposed perpendicularly with respect to each other, the outer conductor of the closed line being galvanically connected with a conductor of the open line, the inner conductor of the closed line projecting as an aerial beyond the outer conductor and partially penetrating into the field space of the open line, a metal tube enclosing the open line and galvanically connected 25 with the outer conductor of the closed line, an ultra-short wave tube, concentric cylindrical conductors limiting the tube and forming a resonator being galvanically connected with the conductors of the closed line and di-pole aerials of the length M2 coupled with the open energy line.

WALTER. DALLENBACH. 

